Damage can occur when water pressure is too high

Posted6/21/2020 7:00 AM

Q: I fail to understand how home inspectors come up with their findings. I mean, some of you guys are loose cannons with your opinions, and this can really mess up a real estate deal. A few weeks ago, this home inspector cited my house for having high water pressure. According to his report, the pressure is 90 pounds, supposedly 10 pounds over the legal limit. So I called the local water company, and they said that pressures as high as 125 are legal. What do you think of that?

A: The problem here is a conflict of standards. Water companies are regulated by public utility commissions, while residential plumbing must comply with the Uniform Plumbing Code. Accordingly, the water companies in some states are allowed to provide pressures as high as 125 pounds per square inch (psi) to the service meters at subject properties. However, that is where the bureaucratic authority changes hands.


Permissible water pressures within a building are not regulated by public utility commissions, but rather by local building and planning departments, and this involves enforcement of the Uniform Plumbing Code. According to the code, the water pressure in a dwelling may not exceed 80 psi. If the pressure happens to be higher, the installation of a pressure regulator is a legal requirement.

The reason for maintaining pressures at or below 80 psi is to prevent leakage and possible water damage within a building. The manufacturers of many plumbing fixtures and appliances design and test their products to operate at normal pressure levels, that is, within plumbing code parameters. Excessive pressure can cause an appliance fitting to leak or detach. If a connection should fail inside a dishwasher, for example, the result could be water damage throughout the home.

Fortunately, the high water pressure in your home was discovered by your "loose cannon" home inspector. You might give that inspector a call to express belated thanks.

Q: Last winter we installed strips of fiberglass insulation between the rafters in our attic, but our heating and cooling bills remained the same as they had been the previous year. If attic insulation doesn't help, what can we do to reduce the costs of heating and cooling our home?

by signing up you agree to our terms of service

A: If you installed attic insulation between the roof rafters, it's no wonder you experienced no improvement in energy efficiency. Attic insulation should be placed between the ceiling joists, not the rafters.

The purpose of attic insulation is to contain heat within the living areas of your home during the winter, and to keep the hot air in your attic from entering the living area during the summer. This means that the exchange of heat must be stopped at the ceiling, not the roof. When insulation is placed between the roof rafters, heat is allowed to penetrate through the ceilings. The solution is to reposition the fiberglass batts in your attic. And be sure to wear adequate breathing protection when handling fiberglass.

• To write to Barry Stone, visit him on the web at www.housedetective.com, or write AMG, 1776 Jami Lee Court, Suite 218, San Luis Obispo, CA 94301.

© 2020, Action Coast Publishing

Article Comments ()
Guidelines: Keep it civil and on topic; no profanity, vulgarity, slurs or personal attacks. People who harass others or joke about tragedies will be blocked. If a comment violates these standards or our terms of service, click the X in the upper right corner of the comment box. To find our more, read our FAQ.